Barrier wall for manhole construction



July 3, 1962 H. J. SIEBEN 3,041,838

BARRIER WALL. FOR MANHOLE CONSTRUCTION Filed May 8, 1959 2 Sheets-Sheet l INVENTOR. HERSCHEL d.Su= BE.N

BY MW ATTORNEY July 3, 1962 H. J. SIEBEN 3,041,838

BARRIER WALL FOR MANHOLE CONSTRUCTION Filed May 8. 1959 2 Sheets-Sheet 2 INVENTOR.

HERSCHEL dSlEBEN 2m w. Mad

ATTORNEY United States Patent Ofilice 3,h4l,838 Patented July 3, 1962 3,941,338 BARRIER WALL FOP; MANHGLE CGNSTRUUTEQN Herschel J. diehen, 99% Lee lire-lo, Kansas Qity, Mo. Filed May 8, 11959, Ser. No. Sllfiii 2 Claims. (Cl. el -41) This invention relates to barrier walls for use in the construction of manholes.

In constructing a manhole it has been the practice to dig a hole of sufiicient diameter with sloping sides so that the walls of the excavation will not cave in on the manhole being constructed and the men constructing it. In cases where a large excavation of this type was impossible or impractical a barrier wall made by driving sheet metal pilings has been used. Both methods have serious disadvantages. A large excavation is obviously costly and in some cases impossible. The use of sheet metal pilings is also costly since it requires heavy equipment to install and is difficult to remove after the manhole has been built.

The object of this invention, therefore, is to provide a barrier wall which is relatively inexpensive and easy to install and which can be readily removed after the manhole has been constructed.

Such a barrier wall is made from a frame having a pair of spaced ring members fastened together by a plurality of vertical supports. The frame is lowered into an excavation with one ring lying flat against the bottom thereof. A third ring having means for adjusting its diameter is supported from the upper ring of the frame.

A plurality of elongated wall members are then lowered between the adjustable ring and the upper ring of the frame and arranged side by side around the frame. The wall members are driven into the ground and the adjustable ring is tightened to clamp the upper ends of such members between the adjustable ring and the upper ring of the frame to thereby form a solid barrier wall around the construction area.

A manhole can then be constructed in an excavation of relatively small diameter without fear of damage or injury. After the manhole is finished the barrier wall is easily removed for further use by simply loosening the adjustable ring and pulling the Wall members and frame vertically out of the excavation.

Other objects and advantages will be pointed out in, or be apparent from the specification and claims, as will obvious modifications of the single embodiment shown in the drawings, in which:

FIG. 1 is a perspective view of the barrier wall construction of my invention with only two of the wooden wall members installed;

FIG. 2 is a vertical sectional view of an excavation in which a barrier wall has been constructed in accordance with my invention;

FIG. 3 is a top plan view of the frame for the barrier wall;

FIGS. 4 and 5 are sectional views of the vertical and horizontal members of the frame showing the couplings employed to facilitate assembly and disassembly of the frame; and

FIG. 6 is a fragmentary view of the frame showing one of the hooks which serve to support the adjustable ring on the upper ring of the frame.

Referring now to the drawings, assume that it is desired to construct a four-foot manhole llll (inside dimensions) having 8 inch brick walls. The first step is to dig a hole 12 of approximately ten feet in diameter. This dimension will vary with the type of soil in which the manhole is to be constructed but will in all cases be considerably less than where no barrier wall is used.

The next step is to lower a frame, as shown in FIG. 1, into the excavation. The frame is self-supporting and consists of a pair of spaced support and guide rings 14 and 16 fastened together by a plurality of equally spaced vertical rods or supports 13. Rings 14 and 16 and rods 1% may be made from any suitable material such as oneinch extra heavy steel pipe as shown in the drawings. The frame can be made in sections for ease of storage and shipment by the use of right and left hand couplings 2%) installed in the upper and lower rings and the vertical supports as shown in FIGS. 1, 4 and 5. A circular ring or belt 22. having a means 23 for adjusting its diameter is supported from the upper ring 16 by a plurality of hooks 24, as shown in FIGS. 1, 3 and 6. The function of adjustable ring 22 will be explained more fully hereinafter.

The frame is lowered into the excavation by means of lugs 26 welded to the top or guide ring 16 as shown with the lower or support ring 14 fiat against the bottom of the ex avation. A circular barrier Wall is then formed by a plurality of wall members 28 which are lowered between adjustable ring 22 and upper ring 16 of the frame and then driven into the ground around the lower ring 14. Wall members 23 are preferably 2 x 8 inch wooden boards but may be of any suitable size and material. Apertured brackets 34} are fitted on the upper ends of boards 28 to facilitate driving them into the ground and their removal therefrom.

After the wall boards 28 are installed ring 22 is tightened by adjusting means 23 to thereby clamp the upper ends of the boards between the top or guide ring 16 of the frame and the rod 22 forming a solid barrier around the construction area. The manhole It) can then be constructed without fear of the walls of the excavation crumbling and falling on the manhole being constructed or the men constructing it.

The adjusting means shown in FIGS. 1 and 13 includes a bracket 32 in which one end of ring 22 is anchored and in which the other threaded end 34 of the ring is slidably mounted for tightening by means of a nut 36. This adjustingmeans is only one of many types which may be employed to produce the desired results. Similarly, the adjustable ring 22 may take different forms. It: has been found that a ring made from inch steel rod gives good results. However, it should be understood that rings of different size and material would be suitable. The ring need not be rigid but could, for example, be made from steel cable if desired. The use of steel cable would be particularly well adapted for use with a frame having square or rectangular shaped upper and lower rings.

After the manhole is constructed the boards and frame are easily removed by first releasing ring 22 and then pulling the boards and frame vertically out of the excava tion for use at a different site.

The frame is preferably of about four feet in height which makes it suitable for construction of a manhole of about eight feet in height. For manholes of greater height a pair of four-foot frames can be used one on top of the other with longer wall boards to provide a barrier of sufficient height.

Although but one embodiment of the present invention has been illustrated and described, it will be apparent to those skilled in the art that various changes and modifications may be made therein without departing from the spirit of the invention or from the scope of the appended claims.

I claim:

1. A barrier wall for constructing manholes comprising, a self-supporting frame having first and second rigid rings spaced from each other by a plurality of vertical supports fastened between said rings, said rings being of substantially the same diameter and parallel to each other with said first ring lying flat on the ground, a plurality of boards arranged vertically side by side around said spaced rings with the ends thereof sticking into the ground, a third ring encircling the upper ends of said boards, said third ring having means for adjusting its diameter so it can be drawn up tightly around said boards to hold them tightly against said second ring to thereby form a solid barrier wall, said third ring supported from said second ring around the outside of said frame by a plurality of hooks.

2. A barrier wall comprising a frame having a support member, a guide member, and a plurality of spaced vertical members supporting said guide member above said support member, a plurality of elongated wall members arranged vertically side-by-side around the outside of said guide member to form a wall, and belt means supported from said guide member and encircling the upper portion of said Wall members, said belt means including a rigid ring supported by said guide member and means for adjusting the diameter of said rigid ring so that said rigid' ring can be tightened around said Wall members to hold said wall members against said guide member.

References Cited in the file of this patent UNITED STATES PATENTS 

